How can I stop my animation looping (Dope Sheet)
You can create a script with the following code. Run it once after you start blender and now the playback will stop at the value you have in the end box (ending range).

import bpy

def stop_playback(scene):
    if(scene.frame_current == scene.frame_end):
        bpy.ops.screen.animation_cancel(restore_frame=False)

bpy.app.handlers.frame_change_pre.append(stop_playback)